AirPods Pro 2 without iPhone

I got some new AirPods Pro 2 buds for Christmas. So far I like them a bunch. I have hearing aids I never really got comfortable with (figuratively and literally) and was interested in the AirPods as hearing aids.

I don't have an iPhone (I know, boo hiss), but do have an M1 MacBook Pro. Accordingly, I could do everything necessary except the initial hearing aid setup. I tried doing the hearing test on my brother-in-law's iPhone, but never got that to work. I eventually just purchased a used iPhone 12 Mini, got the most recently hearing test graph from my audiologist, and punched the numbers in manually. That worked fine. I horsed around with the iPhone a bit, but eventually reset it and went back to my Pixel 6.

I'm curious to know how the AirPods juggle the various functions: hearing aids, noise cancellation, music, phone. Suppose I'm out and about listening to some tunes on my phone, go into a market and want the hearing aid functionality. When I pause the music will the hearing aid function kick in automatically? What about the noise cancellation? Can I turn it off in a setting where I want the background sound/noise? Will I be able to adjust any settings when away from my Mac? I see "Press and hold to switch between listening modes" in the tech specs, but it's not clear what the various modes are or what the tones mean.